Canadian soldiers take part in Operation Janubi Tapu 2 in the Zhari district of Kandahar province this week. (Combat Camera)

Canadian soldiers have just completed one of their largest operations ever in southern Afghanistan, killing 21 insurgent fighters and capturing several others, according to the Canadian military.

Operation Janubi Tapu 2 — or "southern vulture" — was aimed at reducing the ability of the insurgents to attack Kandahar city from the nearby Zhari district, the military said.

The head of the Canadian battle group, Lieut.-Col. Roger Barrett, called the operation a complete success.

More than 500 soldiers, most of them Canadians, along with some British commandos, joined Afghan national security forces and their U.S. mentors in the three-day attack.

Fifteen militants were killed in an early morning raid and six were detained Wednesday, he said, while another six were killed in an air strike while setting up a mortar Thursday morning.

Soldiers detained 20 others during the operation, as well as locating and destroying several weapons caches.

There were no Canadian injuries.

13 Afghan troops killed in ambush

Meanwhile, in northwestern Afghanistan, Taliban insurgents killed 13 Afghan troops in an ambush of their convoy in northwestern Afghanistan, while NATO-led troops fired on insurgents inside Pakistan, officials said Friday.

More than 300 militants attacked the Afghan convoy, which was transporting 47 vehicles for units in Bala Murghab district of Badghis province late Thursday, said Naeem Khan, a border police official.

In a several-hour battle, 13 Afghan soldiers and policemen were killed and 11 others were wounded, said Abdul Ghani Sabri, the deputy provincial governor.

Seven Taliban fighters were also killed, Sabri said.

Insurgent attacks in Afghanistan are up 40 per cent from 2007, military officials say. A tally of official figures provided to the Associated Press show that more than 5,400 people have died in insurgency-related violence this year. Most of the casualties are suspected militants.

With files from the Canadian Press and the Associated Press